Study on Urban Construction Land Suitability Evaluation in Southwestern Mountainous Areas of Yunnan Province Based on the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" : A Case in Lianghe County

According to the particularity of towns＇ construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using ＂ex- treme conditions method＂ and ＂suitability index method＂, and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County＇s main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11：49：40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China.

Research on Ecological Livable Urban Construction in Small and Medium Cities of China——A Case Study of Huaihua City

The paper has analyzed the concept of ecological livable city,considered that small and medium cities as the major pattern of China's urbanization are more likely to become ecological livable cities compared with large cities.Based on the actual situation of Huaihua City,it has pointed out its advantages in transport,ecology,foundation and national characteristic,and analyzed existing problems in the construction of ecological livable city from the perspective of urban eco-environment.It considers that its urban ecological planning is to be perfect,urban environment pollution is still serious and people's consciousness for environmental protection is to be improved.On this basis,relevant suggestions have been proposed for ecological livable urban construction in Huaihua City,emphasizing it should perfect urban ecological planning,enhance environmental pollution treatment,intensify environmental protection education,and improve people's consciousness for environmental protection.

Ecoeconomic construction and sustainable development of natural scenery cities in China

As a country of rich natural resources, China has many beautiful natural scenery resorts. Due to rapid growth in tourism, cities of various sizes have been formed with the development of these scenery resorts. The rapid growth of these cities, while bringing benefits to local people, also produces some serious problems. In this paper, general introduction is given to the studies of natural scenery cities in China. Types and functions of scenery cities in China are discussed, and their relation to tourism and urban ecosystem is defined. Special attention is given to the local and nationality factors in the construction of these cities. The problems the people are now facing in the construction of the natural scenery cities are analyzed and solutions presented.

Application of 3D Digital Modeling Technology in the Construction of Digital Cities

The concepts of “digital twins”, “3D real scene”, “metacosm” and others were the technical paths for building digital cities with the development of emerging surveying and mapping science and technology, which was to build a digital and virtualized city that matched the real physical world, to achieve a one-to-one correspondence between all elements of the physical world and the digital virtual world. And one of its basic geographic information data was a highly similar, virtual simulation of the 3D real scene. After exploring the traditional manual 3DsMax modeling, UAV low-altitude digital oblique photogrammetry modeling, airborne laser scanning modeling and other single modeling technologies, this paper discussed the 3D digital modeling technology used by the UAV airborne laser scanning point cloud and low-altitude digital oblique photogrammetry for complementary integration, constructing the 3D scene of the digital city. This paper expounded the technical route and production process of 3D digital modeling, in order to provide technical references for related projects.

Discussion on the Problems and Path of Characteristic Town Construction in Underdeveloped, Resource-Based Cities: A Case Study of Ganzhou City

Characteristic towns as a characteristic industry are one of the important measures of China's new urbanization strategy. The construction of characteristic towns in different regions needs to pay attention to regional differentiation. At present, the research on characteristic towns focuses on the developed the developed central and eastern regions. There are still few studies on characteristics towns in underdeveloped areas. Starting from the analysis of the concept of the characteristic town, this paper sorted out the general situation of the construction of characteristic towns in China based on the existing research literature, selected Ganzhou City for research, pointed out there were "two restrictions and two singles" in the construction of characteristic towns in Ganzhou City, and clarified that the characteristic towns of Ganzhou City should adhere to the construction path of "two characteristics and two integrations", with a view to providing a useful reference for in Ganzhou City the construction of characteristic towns, industrial transformation and upgrading, and poverty alleviation in such underdeveloped, resource-based cities.

Multidimensional perspectives on the construction of ecological civilized cities

A city is an organic system. The construction of an ecological civilized city is a systematic project, which calls for reasonable, organic and sustainable construction of cities in all respects from multidimensional perspectives of planning and design, policies and systems, industrial economy, scientifi c and technological innovation, culture and education and so on, among which, the planning and design is the overall positioning; the policies and systems are the fundamental guarantee; the industrial economy is the key support; the scientifi c and technological innovation is the core support and the culture and education is the humanist motivation.

Construction land expansion and influencing factors of typical river valley cities in Northeast China: Taking Jilin City as an example

Jilin City is a typical river valley city in Northeast China.In this paper,the authors studied the spatial and temporal expansion characteristics of the built-up areas in Jilin City from 1990 to 2020 using the analysis of expansion speed and strength,fractal dimension,barycenter coordinate transfer index and sector analysis.The ultimate-goal is to analyze the driving and restrictive factors that affect the spatial expansion of river valley cities.The results indicate that(1)the expansion speed of urban land in Jilin City has been re-latively slow in the past 30 years,while only slightly faster in 2010–2020;(2)in the spatial dimension,Jilin City mainly expanded to the south,then to the west,and extensive expansion has resulted in complex mor-phology with little stability and compactness;(3)the expansion is affected by multiple factors,of which the positive factor is industrial development,while the restrictive factors include natural factors,population loss,etc.This study provides a case for the formulation of land use policies and land space planning in river valley cities.

Study on the Construction Path of Characteristic Small Cities and Towns from the Perspective of Supply-side Reform——Taking Zushan Town as an Example

Characteristic small cities and towns are the new vehicle for advancing new urbanization construction and supply-side reform.Zushan characteristic towns focus on tourism vacation,ecological livability,integration of production and cities,cultural heritage,poverty alleviation and other functions,and focus on building a new type of"product,city,and people"trinity,is a new benchmark for industrial transformation and upgrading.This article uses field surveys,interviews,and other methods to investigate the status quo of the construction of small towns with Zushan characteristics.Based on this,SWOT analysis of small towns is carried out,and the disadvantages and threats to its development are determined from the nature of towns and cities,infrastructure construction,and townships.Five suggestions were made for the construction of capital,the cultivation of special industries,and the detennination of the main body of urban construction.

Protection, Development and Utilization of Industrial Heritage Under the Background of Transformation of Exhausted Cities: A Case Study of Construction Planning of Anyuan National Mine Park

Firstly,the status quo of Pingxiang City as a resource-exhausted city was introduced firstly,and then the development situation of Anyuan Coal Mine,which is the representative of traditional coal industry in Pingxiang,was summarized.Moreover,the classification and value of mining heritage were analyzed,and it is proposed that the development of mine heritage tourism and urban transformation should be combined.The planning of Anyuan National Mine Park under the background of urban transformation was analyzed to provides an idea for the protection and utilization of industrial heritage.

Practical Teaching Design of Ecotourism Course under the Construction of Park Cities:A Case Study of Qinglong Lake Ecological Wetland Park

The construction of park cities makes it possible for the popularization of ecotourism,and lays resource conditions and product foundation for the practical teaching of ecotourism course.In this paper,natural ecological resources and ecological leisure and recreation in Qinglong Lake Ecological Wetland Park were analyzed,and a series of practical teaching projects can be designed based on ecological cognition education,ecological responsibility,ecological experience,ecological environmental protection publicity and ecological tourism scenic spot management,as well as the teaching requirements of ecotourism course.

“Waste-free Cities”Construction and Carbon Emission Reduction in China:Based on the Perspective of Circular Economy

Solid waste and carbon dioxide are important elements of environmental governance.Under the background of carbon peaking and carbon neutrality goals,the research on whether and how to promote the construction of“no waste cities”and carbon emission reduction is of great significance in China.The generation of solid waste and greenhouse gases such as carbon dioxide has the same origin,which can be well coordinated to promote environmental governance.

Analysis on the Necessity and Feasibility of Implementing the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" in Yunnan Province

Yunnan is one of the most typical mountalnous provinces in western Chi-na. For the geographical features of mountalnous areas accounting for most parts and fIatIand areas accounting for smal parts, the contradiction between farmIand protection and construction guarantee is very prominent. In the first half of 2011, Yunnan Province estabIished creativeIy the strategy of ＆quot;protecting farmIand in fIat-Iand areas and constructing mountalnous cities＆quot; （hereinafter referred to as the strat-egy of ＆quot;constructing mountalnous cities＆quot;）, which was almed at protecting effectiveIy the Iimited and high quality arabIe Iand resources in fIatIand area and providing new construction area for new type of urbanization and industrialization, so as to achieve win-win situation between arabIe Iand protection and urbanization deveIopment. Im-pIementing this strategy in Yunnan Province is feasibIe, malnIy in the Iarge deveIop-ment potentials in the gentIe gradient between 8° to 25°. The gentIe sIope area be-tween 8° to 25° occupies 51% of the total Iand area in Yunnan Province, which is almost 140 times of the area of urban construction Iand in Yunnan in 2009. The surrounding areas of fIatIand or maln town in most counties （cities, regions） dis-tribute with different sizes of Iow hiI s and gentIe sIopes, thus mountalnous construc-tion Iand reserves are abundant, which benefits for impeI ing the strategy of ＆quot;con-structing mountalnous cities＆quot; in the Iight of Iocal conditions.

The Scale of Constructing Mountainous Cities in Yunnan Province based on “Benchmark” Farmlands

In 2011, Yunnan provincial committee and government proposed the strat- egy of constructing mountainous cities in order to protect farmlands and guarantee crop safety, which makes full use of hills and gentle-slopes and transforms land use pattern. However, social and economic development performs unevenly in Yun- nan, supplemented by varied geographical conditions, so that constructing mountain- ous cities should proceed as per local conditions. The research proposed the con- trol of constructing mountainous cities provided crop safety under the principle of farmland protection and measured the quantities of demanded construction lands ac- cording to science of population prediction and ekistics, based on which the control scales of constructing mountainous cities were determined by multiplying basic farm- land coefficient and the area of newly increased construction lands. The research is of significance for guiding the construction of mountainous cities and avoiding the occupation of construction lands on farmlands.

Subsurface multi-physical characterization of mountain excavation and city construction in loess plateau with a fiber-optic sensing system

Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the artificial land is essential,yet challenging.Here,we use an improved fiber-optic monitoring system for its subsurface multi-physical characterization.The system enables us to gather spatiotemporal distribution of various parameters,including strata deformation,temperature,and moisture.Yan’an New District was selected as a case study to conduct refined in-situ monitoring through a 77 m-deep borehole and a 30 m-long trench.Findings reveal that the ground settlement involves both the deformation of the filling loess and the underlying intact loess.Notably,the filling loess exhibits a stronger creep capability compared to underlying intact loess.The deformation along the profile is unevenly distributed,with a positive correlation with soil moisture.Water accumulation has been observed at the interface between the filling loess and the underlying intact loess,leading to a significant deformation.Moreover,the temperature and moisture in the filling loess have reached a new equilibrium state,with their depths influenced by atmospheric conditions measuring at 31 m and 26 m,respectively.The refined investigation allows us to identify critical layers that matter the sustainable development of newly created urban areas,and provide improved insights into the evolution mechanisms of land creation.

Properties and Characteristics of Regolith-Based Materials for Extraterrestrial Construction

The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of its good sustainability and acceptable economic cost,triggering the development of various types of extraterrestrial construction materials.A comprehensive survey and comparison of materials from the perspective of performance was conducted to provide suggestions for material selection and optimization.Thirteen types of typical construction materials are discussed in terms of their reliability and applicability in extreme extraterrestrial environment.Mechanical,thermal and optical,and radiation-shielding properties are considered.The influencing factors and optimization methods for these properties are analyzed.From the perspective of material properties,the existing challenges lie in the comprehensive,long-term,and real characterization of regolith-based construction materials.Correspondingly,the suggested future directions include the application of high-throughput characterization methods,accelerated durability tests,and conducting extraterrestrial experiments.

Understanding the Relationship Between Shrinking Cities and Land Prices:Spatial Pattern,Effectiveness,and Policy Implications

Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas.

A comprehensive review of lunar lava tube base construction and field research on a potential Earth test site

The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission.Lunar lava tubes are special underground caves formed by volcanic eruptions and are considered as ideal natural shelters and scientific laboratories for lunar base construction.This paper begins with an in-depth overview of the geological origins,exploration history,and distribution locations of lunar lava tubes.Subsequently,it delves into the presentation of four distinctive advantages and typical concepts for constructing bases within lava tubes,summarizing the ground-based attempts made thus far in lunar lava tube base construction.Field studies conducted on a lava tube in Hainan revealed rock compositions similar to those found during the Apollo missions and clear lava tube structures,making it a promising analog site.Lastly,the challenges and opportunities encountered in the field of geotechnical engineering regarding the establishment of lunar lava tube bases are discussed,encompassing cave exploration technologies,in-situ testing methods,geomechanical properties under lunar extreme environments,base design and structural stability assessment,excavation and reinforcement techniques,and simulated Earth-based lava tube base.

Research Progress and Prospects of Total Factor Productivity in the Construction Industry

The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry.

Planning and construction of Xiong’an New Area(city of over 5 million people):Contributions of China’s geologists and urban geology

China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei region.From 2017 to 2021,the China Geological Survey(CGS)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this area.The achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally visualized.China’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and management.The future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(ESS)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area.

A Study on the Symbol-Based Narrative in the International Communication of Cities

Cultural symbols,a manifestation of cities’cultural resources,are not only signs that frame concepts but also forms that express meanings.Exploring the international communication of cities from the perspective of symbols,this paper analyzes in depth how cities create their cultural symbols in the dynamic process of international communication in an era of symbol-based digital media,and how they develop their narratives and explain meanings through the dissemination of symbols when telling their stories to international audiences,thus enhancing the efficiency and effectiveness of their international communication efforts.